Vaporizing pressure regulators are used to regulate fluid pressure and at the same time to maintain a predetermined fluid temperature. For example, vaporizing pressure regulators are used as part of a sample conditioning systems for on-line gas chromatographs to reduce the fluid pressure and to maintain the temperature of the fluid stream high enough to keep it in its gas phase. As another example, these types of regulators are also used to vaporize liquid hydrocarbons being analyzed in hydrogen sulfide detectors or other analytical equipment.
As noted above, the regulator must be able to reduce the fluid pressure and maintain a predetermined fluid temperature. Many of the regulators utilize complex heating arrangements that are relatively expensive and difficult to control. For example, one known regulator uses a tube that forms part of the fluid flow path and a heating oil bath surrounding the tube. The tube/oil bath arrangement is not only expensive and difficult to control, but it presents difficulty and expense in sealing the tubing and can, also, result in reliability problems.